The Moa

It is just a big dumb bird that is basically an ostrich but-
IF YOU KILL THEM THIS WILL HAPPEN:
Just a joke but they are cool.
Kill to many and a special Moa will become an elite commander and kill you. Garry will hunt you down!

They run away from you, you can kill them and that's it.
Shoot them in the head with pistols and throw plasma grenades at them.

There are 2 achievements about these birds,
1: On Exodus there is an Achievement for looking at moa burger. Yumm...
2: Kill 7 moa on the first Mission on Halo Reach. You will not only get an achievement but also a name plate for killing 7 of them.
3: They have a cut attack animation for probably fighting you of or something. Thank you to someone in the comments!
4: Pringles made some chips that taste like Moa!

There it is, all about these animals.
Did I miss anything? tell me in comments